Problem: Solve for $x$ : $7x + 1 = 9x + 3$
Answer: Subtract $7x$ from both sides: $(7x + 1) - 7x = (9x + 3) - 7x$ $1 = 2x + 3$ Subtract $3$ from both sides: $1 - 3 = (2x + 3) - 3$ $-2 = 2x$ Divide both sides by $2$ $\dfrac{-2}{2} = \dfrac{2x}{2}$ Simplify. $-1 = x$